Tobias Bjerrome Ahlin, an interface designer at Spotify, is a big believer in skeuomorphism. Whereas Apple is a strong advocate of this design concept, Microsoft is clearly moving in the exact opposite direction, while Android is in the process of moving away from skeuomorphism entirely, to a more digital experience. As a passionate hater of skeuomorphism in UIs, I found Ahlin's examples to be a bit weak.

But still not the only tradition (trackers, most notably; and I believe that graphical signal flow editors look more like "digital" diagrams, typically not attempting very much to look and feel like manipulating cables and plugs on screen)